Worms will eat their garbage 2009.04.15

It just makes a lot of sense, says waste disposal educator Sarah Archer. You can put materials back into the earth rather than dump them in a landfill.

Worms have been eating her garbage for the past 15 years, converting it into compost for garden use. A couple of bins in her basement handle all of her leftover fruit and vegetable scraps.

During the week, Archer works with municipalities to develop waste reduction and recycling programs, but Saturday at Hidden Lake Gardens she faced a different audience—20 people from Lenawee County and beyond ready to become vermicomposting enthusiasts, or, to put it more plainly, worm farmers.

The registration fee for the workshop covered the cost of a 14-gallon heavy duty Rubbermaid bin, a spray bottle, a small garden fork and a package of red worms—at least a thousand. On top of that came Archer’s expertise in the art of maintaining a happy colony of worms.

“They’re amazing little creatures and very important to the planet,” she said.

In their natural environment, red worms typically live a year.

“They’ll live three to five years in a bin, so you’re doing them a favor,” she said.

The worms in her bin are descendants of the group she bought initially. If properly cared for, they’ll replenish themselves generation after generation.

The red worm is a surface-dwelling creature—perfect for the work to be done in a compost bin—unlike the large night crawler that burrows deep into soil, sometimes to depths of 12 feet.

“It’s not only worms doing the work,” Archer said. “There are lots of smaller organisms. Worms can’t do their jobs until the others do theirs.”

Springtails, fungi, bacteria, microarthropods and other organisms handle the initial work of breaking down organic material, then the worms take over, slurping the food through their toothless mouths. When it exits through the other end, the worm castings serve as a rich compost ready to be mixed with garden soil.

Getting it ready

After Archer’s introduction to the topic, bins were distributed and students were instructed to tear newsprint into strips about an inch wide.

Take a standard size newspaper, folded in half, and tear downward from the fold. This leads to the easiest tearing and gives the newsprint the best water retention. (For a tabloid size paper such as the Observer, tear in the opposite direction).

Cardboard works well, too, but Archer avoids office paper. Leaves are fine, also, but she prefers to recycle trash.

Students tore strips from 10 sections, then fluffed them up to separate the pieces. With spray bottles, students dampened the paper until it changed to a gray color—enough to get rid of the crunch of newsprint, but not enough to make it soggy and leave standing water in the base of the bin.

Food will moisten the mix as it decomposes and additional water can be sprayed in later, if needed. Proper moisture content will prevent fruit fly growth.

Next came the package of worms. The cardboard package was opened, the worms were dumped into the bin and the cardboard was torn into pieces for recycling.

Once at home, students were to place not more than a 12-ounce container of food scraps into the bottom of the bin and cover it with bedding—another important means of controlling fruit flies.

That initial container of food should be sufficient for the first couple of weeks, she said, while the worms become acclimated to their new home. Add an eggshell, also, plus another one a few months later. It’s a good source of calcium carbonate—essential for worm production.

Once the composting gets underway, Archer adds three to five pounds of food scraps a week.

“For the first month, you’ll see only bedding,” Archer said, but eventually the compost begins to form. In her bin, there’s a thin layer of bedding over several inches of compost.

When needed, additional bedding should be fluffed and added to the top.

The speed of the composting process depends on the amount of available food and the temperature. The 70° range is ideal; a cool basement is fine, but the process will go slower.

When the compost reaches the ridge line in the bin—almost three-fourths full—it’s time to empty the bin onto a tarp and remove the compost for garden use. The worms don’t like light and will burrow down as more and more compost is removed.

Eventually there’s little left but worms and then it’s time to start again, so there will always be worms eating your garbage.

As a waste diversion specialist, Sarah Archer covers a variety of topics each week as she helps cities and businesses find better ways to handle their waste.

Worm composting hints

• In addition to fruit and vegetables, dry cereal, pizza crust and other bread is OK to add. Citrus products, coffee grounds and tea bags can be added only in a limited amount due to the acidity.

• Broccoli stems and other thick remains from the brassica family of vegetables are slow to decompose. If they aren’t first ground up, they might be better placed in an outdoor compost bin.

• Food can be added every day or saved and added once a week.

• Keep a spray bottle near the bin to moisten if the bedding appears dry.

• All those living creatures generate heat. The warm, moist air can be felt when a bin is opened.

• Experiment: See how worms handle a corn cob or an avocado pit. “It’s the coolest thing to go back and look at it after a while,” Sarah Archer said about corn cobs. Worms can be found curled up inside the cob as it decomposes.

• Don’t use the nitrogen-rich compost directly on a house plant or the roots may be burned.

• There’s no worry about too many worms because the population will moderate itself. One way of harvesting the compost is to remove the top two-thirds and dump it—worms and all—onto the garden.

• Looking for a good vermicomposting book? Sarah Archer’s favorite is the old classic by the late Mary Applehof of Michigan: “Worms Eat My Garbage.”